FP Flash With FP (Focal Plane) flash, you can synchronise the flash at all shutter speeds even at the EOS-3's top speed of 1/8000 sec. Just set the Speedlite 550EX to FP flash and the camera switches over automatically. With a fast sync speed, you can use a large aperture to obtain better background blur or you can use fill flash for a fast moving subject in daylight. Flash Exposure Bracketing You can bracket three consecutive frames automatically up to -/+ 3 stops in 1/3-stop increments. The flash output changes with each bracketed frame while the background exposure level remains the same. Wide Coverage Speedlite 550EX's flash coverage is wide enough for 24mm to 105mm lenses. Also, the built-in wide panel expands the coverage to 17mm, which is 1mm wider than the built-in wide panel of the Speedlite 540EZ designed for the Canon EOS-1N camera. Multiple Speedlites can obtain lighting effects not possible with a single flash unit. If previously user of the Canon EOS system has to make do with using accessories like the Off Camera Show Cord 2 or TTL Hot Shoe Adapter and other wired TTL connectors for off-camera flash photography, with the EOS-3, the approach is now different. Using the EOS-3 with two or more Speedlites 550EX, Wireless Autoflash is possible. With the Speedlite Transmitter ST-E2, you do not even need a main Speedlite to fire off the other Speedlites 550EX used in the Wireless system. E-TTL Wireless Autoflash Control Up to three groups (for main, fill and background flash) of slave units can be set up. The slave unit's ID is set to A, B or C. The flash output ratio between two Speedlite groups can be adjusted automatically from 8:1 to 1:1 or from 1:1 to 1:8. The flash output of the third Speedlite group can be adjusted through flash exposure compensation. The E-TTL autoflash system controls the total flash output to obtain a correct exposure. Also, when Speedlite 550EX is used with the EOS-3, you can fire a modelling flash to preview the flash effects before shooting the picture. E-TTL Wireless autoflash can also be used with most other Speedlite features such as FE Lock, FP Flash, flash exposure bracketing/compensation and stroboscopic flash. << Back to Main . 1 . 2 . 3 . 4 .